From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Aikar <aikar@aikar.co>
Date: Thu, 28 May 2015 23:00:19 -0400
Subject: [PATCH] Handle Item Meta Inconsistencies

First, Enchantment order would blow away seeing 2 items as the same,
however the Client forces enchantment list in a certain order, as well
as does the /enchant command. Anvils can insert it into forced order,
causing 2 same items to be considered different.

This change makes unhandled NBT Tags and Enchantments use a sorted tree map,
so they will always be in a consistent order.

Additionally, the old enchantment API was never updated when ItemMeta
was added, resulting in 2 different ways to modify an items enchantments.

For consistency, the old API methods now forward to use the
ItemMeta API equivalents, and should deprecate the old API's.

diff --git a/src/main/java/net/minecraft/world/item/ItemStack.java b/src/main/java/net/minecraft/world/item/ItemStack.java
index 1a52db84d9630a095347a85e136a9ad118f77325..d66cc030dcd3d98f57803938c8c06342a028ee88 100644
--- a/src/main/java/net/minecraft/world/item/ItemStack.java
+++ b/src/main/java/net/minecraft/world/item/ItemStack.java
@@ -14,6 +14,8 @@ import java.text.DecimalFormatSymbols;
 import java.util.Collection;
 import java.util.Iterator;
 import java.util.List;
+import java.util.Collections;
+import java.util.Comparator;
 import java.util.Locale;
 import java.util.Map.Entry;
 import java.util.Optional;
@@ -153,6 +155,23 @@ public final class ItemStack {
         return this.getItem().getTooltipImage(this);
     }
 
+    // Paper start
+    private static final java.util.Comparator<? super CompoundTag> enchantSorter = java.util.Comparator.comparing(o -> o.getString("id"));
+    private void processEnchantOrder(@Nullable CompoundTag tag) {
+        if (tag == null || !tag.contains("Enchantments", 9)) {
+            return;
+        }
+        ListTag list = tag.getList("Enchantments", 10);
+        if (list.size() < 2) {
+            return;
+        }
+        try {
+            //noinspection unchecked
+            list.sort((Comparator<? super net.minecraft.nbt.Tag>) enchantSorter); // Paper
+        } catch (Exception ignored) {}
+    }
+    // Paper end
+
     public ItemStack(ItemLike item) {
         this(item, 1);
     }
@@ -200,6 +219,7 @@ public final class ItemStack {
             // CraftBukkit start - make defensive copy as this data may be coming from the save thread
             this.tag = nbttagcompound.getCompound("tag").copy();
             // CraftBukkit end
+            this.processEnchantOrder(this.tag); // Paper
             this.getItem().verifyTagAfterLoad(this.tag);
         }
 
@@ -758,6 +778,7 @@ public final class ItemStack {
 
     public void setTag(@Nullable CompoundTag nbt) {
         this.tag = nbt;
+        this.processEnchantOrder(this.tag); // Paper
         if (this.getItem().canBeDepleted()) {
             this.setDamageValue(this.getDamageValue());
         }
@@ -1063,6 +1084,7 @@ public final class ItemStack {
         ListTag nbttaglist = this.tag.getList("Enchantments", 10);
 
         nbttaglist.add(EnchantmentHelper.storeEnchantment(EnchantmentHelper.getEnchantmentId(enchantment), (byte) level));
+        processEnchantOrder(this.tag); // Paper
     }
 
     public boolean isEnchanted() {
diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
index e88df908377450964ae5b6ff97ee97bd2f09c05f..ba70ac49222c517a38e20e86cee1fd38aecb6318 100644
--- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftItemStack.java
@@ -6,7 +6,6 @@ import java.util.Map;
 import net.minecraft.nbt.CompoundTag;
 import net.minecraft.nbt.ListTag;
 import net.minecraft.world.item.Item;
-import net.minecraft.world.item.enchantment.EnchantmentHelper;
 import org.apache.commons.lang.Validate;
 import org.bukkit.Material;
 import org.bukkit.NamespacedKey;
@@ -178,28 +177,11 @@ public final class CraftItemStack extends ItemStack {
     public void addUnsafeEnchantment(Enchantment ench, int level) {
         Validate.notNull(ench, "Cannot add null enchantment");
 
-        if (!CraftItemStack.makeTag(this.handle)) {
-            return;
-        }
-        ListTag list = CraftItemStack.getEnchantmentList(this.handle);
-        if (list == null) {
-            list = new ListTag();
-            this.handle.getTag().put(ENCHANTMENTS.NBT, list);
-        }
-        int size = list.size();
-
-        for (int i = 0; i < size; i++) {
-            CompoundTag tag = (CompoundTag) list.get(i);
-            String id = tag.getString(ENCHANTMENTS_ID.NBT);
-            if (ench.getKey().equals(NamespacedKey.fromString(id))) {
-                tag.putShort(ENCHANTMENTS_LVL.NBT, (short) level);
-                return;
-            }
-        }
-        CompoundTag tag = new CompoundTag();
-        tag.putString(ENCHANTMENTS_ID.NBT, ench.getKey().toString());
-        tag.putShort(ENCHANTMENTS_LVL.NBT, (short) level);
-        list.add(tag);
+        // Paper start - Replace whole method
+        final ItemMeta itemMeta = this.getItemMeta();
+        itemMeta.addEnchant(ench, level, true);
+        this.setItemMeta(itemMeta);
+        // Paper end
     }
 
     static boolean makeTag(net.minecraft.world.item.ItemStack item) {
@@ -216,66 +198,34 @@ public final class CraftItemStack extends ItemStack {
 
     @Override
     public boolean containsEnchantment(Enchantment ench) {
-        return this.getEnchantmentLevel(ench) > 0;
+        return this.hasItemMeta() && this.getItemMeta().hasEnchant(ench); // Paper - use meta
     }
 
     @Override
     public int getEnchantmentLevel(Enchantment ench) {
-        Validate.notNull(ench, "Cannot find null enchantment");
-        if (this.handle == null) {
-            return 0;
-        }
-        return EnchantmentHelper.getItemEnchantmentLevel(CraftEnchantment.getRaw(ench), handle);
+        return this.hasItemMeta() ? this.getItemMeta().getEnchantLevel(ench) : 0; // Paper - replace entire method with meta
     }
 
     @Override
     public int removeEnchantment(Enchantment ench) {
         Validate.notNull(ench, "Cannot remove null enchantment");
 
-        ListTag list = CraftItemStack.getEnchantmentList(this.handle), listCopy;
-        if (list == null) {
-            return 0;
-        }
-        int index = Integer.MIN_VALUE;
-        int level = Integer.MIN_VALUE;
-        int size = list.size();
-
-        for (int i = 0; i < size; i++) {
-            CompoundTag enchantment = (CompoundTag) list.get(i);
-            String id = enchantment.getString(ENCHANTMENTS_ID.NBT);
-            if (ench.getKey().equals(NamespacedKey.fromString(id))) {
-                index = i;
-                level = 0xffff & enchantment.getShort(ENCHANTMENTS_LVL.NBT);
-                break;
-            }
-        }
-
-        if (index == Integer.MIN_VALUE) {
-            return 0;
-        }
-        if (size == 1) {
-            this.handle.getTag().remove(ENCHANTMENTS.NBT);
-            if (this.handle.getTag().isEmpty()) {
-                this.handle.setTag(null);
-            }
-            return level;
-        }
-
-        // This is workaround for not having an index removal
-        listCopy = new ListTag();
-        for (int i = 0; i < size; i++) {
-            if (i != index) {
-                listCopy.add(list.get(i));
-            }
+        // Paper start - replace entire method
+        final ItemMeta itemMeta = this.getItemMeta();
+        if (itemMeta == null) return 0;
+        int level = itemMeta.getEnchantLevel(ench);
+        if (level > 0) {
+            itemMeta.removeEnchant(ench);
+            this.setItemMeta(itemMeta);
         }
-        this.handle.getTag().put(ENCHANTMENTS.NBT, listCopy);
+        // Paper end
 
         return level;
     }
 
     @Override
     public Map<Enchantment, Integer> getEnchantments() {
-        return CraftItemStack.getEnchantments(this.handle);
+        return this.hasItemMeta() ? this.getItemMeta().getEnchants() : ImmutableMap.<Enchantment, Integer>of(); // Paper - use Item Meta
     }
 
     static Map<Enchantment, Integer> getEnchantments(net.minecraft.world.item.ItemStack item) {
diff --git a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
index 911a732065a908545ac6a7c10262980a59bd157e..3f34d3989df1fedf625dc2bd767794067d8a0c06 100644
--- a/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
+++ b/src/main/java/org/bukkit/craftbukkit/inventory/CraftMetaItem.java
@@ -6,6 +6,7 @@ import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
 import com.google.common.collect.ImmutableMultimap;
 import com.google.common.collect.LinkedHashMultimap;
+import com.google.common.collect.ImmutableSortedMap; // Paper
 import com.google.common.collect.Lists;
 import com.google.common.collect.Multimap;
 import com.google.common.collect.SetMultimap;
@@ -23,6 +24,7 @@ import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Base64;
 import java.util.Collection;
+import java.util.Comparator; // Paper
 import java.util.EnumSet;
 import java.util.HashMap;
 import java.util.Iterator;
@@ -33,6 +35,7 @@ import java.util.Map;
 import java.util.NoSuchElementException;
 import java.util.Objects;
 import java.util.Set;
+import java.util.TreeMap; // Paper
 import java.util.logging.Level;
 import java.util.logging.Logger;
 import javax.annotation.Nonnull;
@@ -272,7 +275,7 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
     private List<String> lore; // null and empty are two different states internally
     private Integer customModelData;
     private CompoundTag blockData;
-    private Map<Enchantment, Integer> enchantments;
+    private EnchantmentMap enchantments; // Paper
     private Multimap<Attribute, AttributeModifier> attributeModifiers;
     private int repairCost;
     private int hideFlag;
@@ -283,7 +286,7 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
     private static final CraftPersistentDataTypeRegistry DATA_TYPE_REGISTRY = new CraftPersistentDataTypeRegistry();
 
     private CompoundTag internalTag;
-    final Map<String, Tag> unhandledTags = new HashMap<String, Tag>(); // Visible for testing only
+    final Map<String, Tag> unhandledTags = new TreeMap<String, Tag>(); // Visible for testing only // Paper
     private CraftPersistentDataContainer persistentDataContainer = new CraftPersistentDataContainer(CraftMetaItem.DATA_TYPE_REGISTRY);
 
     private int version = CraftMagicNumbers.INSTANCE.getDataVersion(); // Internal use only
@@ -304,7 +307,7 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
         this.blockData = meta.blockData;
 
         if (meta.enchantments != null) { // Spigot
-            this.enchantments = new LinkedHashMap<Enchantment, Integer>(meta.enchantments);
+            this.enchantments = new EnchantmentMap(meta.enchantments); // Paper
         }
 
         if (meta.hasAttributeModifiers()) {
@@ -387,13 +390,13 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
         }
     }
 
-    static Map<Enchantment, Integer> buildEnchantments(CompoundTag tag, ItemMetaKey key) {
+    static EnchantmentMap buildEnchantments(CompoundTag tag, ItemMetaKey key) { // Paper
         if (!tag.contains(key.NBT)) {
             return null;
         }
 
         ListTag ench = tag.getList(key.NBT, CraftMagicNumbers.NBT.TAG_COMPOUND);
-        Map<Enchantment, Integer> enchantments = new LinkedHashMap<Enchantment, Integer>(ench.size());
+        EnchantmentMap enchantments = new EnchantmentMap(); // Paper
 
         for (int i = 0; i < ench.size(); i++) {
             String id = ((CompoundTag) ench.get(i)).getString(ENCHANTMENTS_ID.NBT);
@@ -546,13 +549,13 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
         }
     }
 
-    static Map<Enchantment, Integer> buildEnchantments(Map<String, Object> map, ItemMetaKey key) {
+    static EnchantmentMap buildEnchantments(Map<String, Object> map, ItemMetaKey key) { // Paper
         Map<?, ?> ench = SerializableMeta.getObject(Map.class, map, key.BUKKIT, true);
         if (ench == null) {
             return null;
         }
 
-        Map<Enchantment, Integer> enchantments = new LinkedHashMap<Enchantment, Integer>(ench.size());
+        EnchantmentMap enchantments = new EnchantmentMap(); // Paper
         for (Map.Entry<?, ?> entry : ench.entrySet()) {
             // Doctor older enchants
             String enchantKey = entry.getKey().toString();
@@ -828,14 +831,14 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
 
     @Override
     public Map<Enchantment, Integer> getEnchants() {
-        return this.hasEnchants() ? ImmutableMap.copyOf(enchantments) : ImmutableMap.<Enchantment, Integer>of();
+        return this.hasEnchants() ? ImmutableSortedMap.copyOfSorted(this.enchantments) : ImmutableMap.<Enchantment, Integer>of(); // Paper
     }
 
     @Override
     public boolean addEnchant(Enchantment ench, int level, boolean ignoreRestrictions) {
         Validate.notNull(ench, "Enchantment cannot be null");
         if (this.enchantments == null) {
-            this.enchantments = new LinkedHashMap<Enchantment, Integer>(4);
+            this.enchantments = new EnchantmentMap(); // Paper
         }
 
         if (ignoreRestrictions || level >= ench.getStartLevel() && level <= ench.getMaxLevel()) {
@@ -1216,7 +1219,7 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
             clone.customModelData = this.customModelData;
             clone.blockData = this.blockData;
             if (this.enchantments != null) {
-                clone.enchantments = new LinkedHashMap<Enchantment, Integer>(this.enchantments);
+                clone.enchantments = new EnchantmentMap(this.enchantments); // Paper
             }
             if (this.hasAttributeModifiers()) {
                 clone.attributeModifiers = LinkedHashMultimap.create(this.attributeModifiers);
@@ -1451,4 +1454,22 @@ class CraftMetaItem implements ItemMeta, Damageable, Repairable, BlockDataMeta {
             return CraftMetaItem.HANDLED_TAGS;
         }
     }
+
+    // Paper start
+    private static class EnchantmentMap extends TreeMap<Enchantment, Integer> {
+        private EnchantmentMap(Map<Enchantment, Integer> enchantments) {
+            this();
+            putAll(enchantments);
+        }
+
+        private EnchantmentMap() {
+            super(Comparator.comparing(o -> o.getKey().toString()));
+        }
+
+        public EnchantmentMap clone() {
+            return (EnchantmentMap) super.clone();
+        }
+    }
+    // Paper end
+
 }
